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Las señales magnéticas desencadenan un extenso reabastecimiento de combustible
T Fransson1, S Jakobsson, P Johansson
1Department of Zoology, Stockholm University, SE-106 91 Stockholm, Sweden. thord.fransson@nrm.se
Nature
|November 2, 2001
Resumen
Las señales magnéticas pueden ayudar a los pájaros cantores jóvenes a prepararse para los largos viajes migratorios. La exposición a un campo magnético simulado llevó a los ruiseñores a aumentar las reservas de grasa, ayudando a la supervivencia a través de barreras ecológicas como los desiertos.
Área de la Ciencia:
- Ornitología Ornitología.
- Migración de los animales Migración de los animales
- Ecología del comportamiento Ecología del comportamiento.
Sus antecedentes:
- Las aves migratorias dependen de las reservas de grasa para cruzar barreras ecológicas que no reabastecen de combustible, como los desiertos y los mares.
- Las aves inexpertas pueden tener dificultades para identificar lugares críticos de escala para reponer las reservas de energía.
Objetivo del estudio:
- Para determinar si las señales magnéticas pueden señalar a las aves a depositar grasa antes de los principales desafíos migratorios.
- Investigando el papel de los campos magnéticos en la navegación aérea y la gestión de recursos.
Principales métodos:
- Los ruiseñores (Luscinia luscinia) fueron capturados antes de su primera migración en Suecia.
- Las aves fueron expuestas a un campo magnético que simulaba una parada en el norte de Egipto, antes del desierto del Sahara.
- La duración de la deposición de grasa fue monitoreada en respuesta al campo magnético simulado.
Principales resultados:
- La exposición al campo magnético simulado extendió significativamente el período de deposición de grasa en el ruiseñor.
- Esto sugiere que las señales magnéticas pueden desencadenar la preparación fisiológica para la migración.
Conclusiones:
- Las señales magnéticas pueden desempeñar un papel crucial en guiar a las aves migratorias inexpertas a los sitios esenciales de reabastecimiento de combustible.
- Este mecanismo podría ayudar a las pequeñas aves cantoras a navegar con éxito y sobrevivir a las grandes barreras ecológicas durante la migración.
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